Pneumatic control apparatus



July 29, 1969 0. B. KIRK 3,457,940

PNEUMATIC CONTROL APPARATUS Filed Feb. 28, 1967 F/GJ FIG. 3

INVENTOR DA V/D 8. KIRK ATTORNEY United States Patent 3,457,940 PNEUMATIC CONTROL APPARATUS David B. Kirk, Hilltown Township, Bucks County, Pa.. assignor to Moore Products Co., Spring House, Pa., a corporation of Pennsylvania Filed Feb. 28, 1967, Ser. No. 619,303 Int. Cl. F15b /00; F15c 3/10 US. Cl. 137-83 1 Claim ABSTRACT OF THE DISCLOSURE A pneumatic detector having a fluid nozzle and a re cciver for fluid from the nozzle with a pick off of subatmospheric pressure generated along the edge of the fluid jet from the nozzle, the subatmospheric pressure providing a signal.

Background of the invention Field 0 the inventiomlhis invention comprises a pneumatic detector employing a nozzle which provides a fluid jet, the fluid jet being interrupted by the presence of an object to provide a detector of the presence of the object, the jet being directed to a receiving location which has a subatmospheric pressure pickup for providing a signal.

Description of the prior art.It has heretofore been proposed to provide a plurality of nozzles, one a supply nozzle and the other a pickup nozzle operating at a lower pressure, the nozzles being supplied from a common source of fluid thereby preventing aspiration or introduction of dirt particularly into the pickup nozzle.

Summary of the invention It is the principal object of the present invention to provide pneumatic control apparatus responsive to the presence or absence of an object, which is simple in construction, reliable in its operation, and in which a fluid jet is employed directed across the expected path of the object.

It is a further object of the present invention to provide simple but effective apparatus for detecting the presence or absence of an object in which a fluid jet directed across the expected path or location of the object, to a receiving location produces an output signal which varies dependent on whether or not an object is in the detection path or location.

It is a further object of the present invention to provide apparatus of the character aforesaid which is free from likelihood of clogging with dirt which would affect its operation.

Other objects and advantageous features of the invention will be apparent from the description and claims.

Brief description of the drawing The nature and characteristic features of the invention will be more readily understood from the following description taken in connection with the accompanying drawings forming part thereof, in which:

FIGURE 1 is a view partly diagrammatic and partly in cross section of a preferred embodiment of the invention;

FIG. 2 is a plan view of the mounting block shown in FIG. 1; and

FIG. 3 is a fragmentary view showing a different form of discharge passageway.

It should, of course, be understood that the description and drawings herein are illustrative merely, and that various modifications and changes can be made in the struc- Description of the preferred embodiment Referring now more particularly to FIGS. 1 and 2 of the drawings, a mounting block 10 is shown which has spaced legs 11 and 12 with a central transverse space 13 therebetween. The space 13 can be bounded by opposed faces 14 and 15 and a connecting face 16.

The block 10, in the leg 11, has a bore 18 therein for the reception of a supply nozzle insert 19 having a nozzle opening 20. The axis of the nozzle opening 20 is located so that a jet from the nozzle opening 20 intersects the space 13, as hereinafter explained.

The bore 18 is connected by a pipe 21 to a suitable source of pressure regulated fluid such as that from an adjustable pressure regulator 22. While any desired fluid may be employed, air can advantageously be used for many purposes.

The leg 12, which provides a jet receiving location for a fluid jet from the nozzle opening 20 has a discharge passageway in communication with the atmosphere which may include a cylindrical bore 25, extending from the face 15 for free discharge of fluid from the jet.

The bore 25 is primarily to provide a location for a connection at which a partial vacuum generated by the jet from the nozzle opening 21 can be utilized. For this purpose a ring or tubular insert 26 can be employed which has a central discharge opening 27 therethrough with a rim or barrier 28 having therebeyond a pressure take off opening 29 in intersecting relation to the opening 27 and communicating with a fluid passageway 31. The passageway 31 extends through the body 10 with a closure plug 30 to facilitate manufacture. The passageway 31 has a fluid connection 32 extending therefrom to any suitable subatmospheric pressure responsive device or devices, such as an indicating gage 33 and a vacuum operated switch 34 for indicating, recording or controlling, as required and desired.

While the bore 25 as shown in FIG. 1, is cylindrical, it can be of any desired shape, such as an open side channel, or flared, as at 25a in FIG. 3, with a barrier 28' and the fluid connection 31 downstream thereof for pressure takeoff.

Fluid, such as air, under pressure is supplied from the pressure regulator 22 through the supply pipe 21 and the nozzle opening 20 in the form of a fluid jet which is delivered across the space 13. The jet has an aspirating action along its exterior and as it passes the barrier 28, and the take off opening 29 entrains the air at that location thereby creating a subatmospheric pressure or vacuum at the opening 29, the passageway 31 and the fluid connection 32 which is effective at the gage 33 and switch 34. The bore 25 or bared bore 251i permits free escape of the jet to the atmosphere.

If now, an object to be detected is moved into the path of the jet from the nozzle opening 20, the jet will be obstructed and will not be effective at the opening 29 so that the pressure at the opening 29 and in the fluid connection 32 and at the gage 33 and switch 34 will rise and will remain at substantially atmospheric level until the jet is again effective at the opening 29.

The apparatus of the present invention can be used in any desired orientation and has been found to be free from clogging with dirt without the necessity for employing any source of purging fluid.

I claim:

1. Pneumatic control apparatus comprising:

a connection to a supply of pressure fluid,

a nozzle with which said connection is in communication,

a receiver spaced from said nozzle with the space therebetween providing an object detecting location,

3 4 said receiver having a surface portion subject to the References Cited aspirating action of said jet from said nozzle along UNITED STATES PATENTS WhICh'SaIdJet'PaSSeS, and a pressure takeolf connection in intersecting relation to 2,907,337 10/1959 Bemporad 137-83 said surface portion, 5 2,947,553 8/1960 Erbguth 137-83 X Said receiver having an inserted ring and 3,071,157 1/1963 Robertson et al. 137-82 X salgfpigezililgergglgre-oif connection having a portion there- WILLIAM s. BURDEN, Primary Examiner 

